NIKON AF-S DX ZOOM-NIKKOR 17-55mm f/2.8G IF-ED

US 2005/0013015 A1 — Takayuki Sensui

14 ELEMENTS / 10 GROUPS
17.55-52.70 mm DESIGN
F/2.89-2.91 DESIGN
83.30°-31.16° FULL FIELD
3 ASPHERICAL SURFACES
PRODUCTION MFD 0.36 m

Focus Mechanism

CONSTRAINED_RECONSTRUCTION: surfaces 6A-10 translate rigidly imageward; D5 increases and D10 decreases by the same solved delta. Close endpoints reproduce the patent Example 5 close block-magnification rows and are fitted to the patent block rows. Because those rows contain a small rear-plane inconsistency, the authored fixed-image-plane model reaches its close conjugate at approximately 0.39897 m; Nikon markets 0.36 m MFD.

Optical Elements (14 physical)

ElementTypeGlass
L1Neg. Meniscus (1× Asph)M-NBF1 catalog equivalent (patent 744495; production supplier unspecified)
L2Biconcave NegativeJ-PKH1 catalog equivalent (patent 519700; production supplier unspecified)
L3Positive MeniscusSF6 class / 805254
L4Biconvex Positive (1× Asph)S-LAL12 (OHARA)
L5Negative MeniscusS-TIH53 (OHARA)
L6Biconvex Positive618634 phosphate-crown class
L7Biconvex Positive (1× Asph)Unmatched (740493; nd=1.739929, vd=49.25)
L8Biconvex PositiveS-TIH53 (OHARA)
L9Biconcave NegativeS-LAH65V (OHARA)
L10Biconcave NegativeS-LAH65V (OHARA)
L11Positive MeniscusJ-FKH1 catalog equivalent (patent 498825; production supplier unspecified)
L12Biconvex Positive618634 phosphate-crown class
L13Biconvex PositiveJ-FKH1 catalog equivalent (patent 498825; production supplier unspecified)
L14Negative MeniscusS-TIH53 (OHARA)